Automatic train-speed-control apparatus



May 6, 1924. 1,492,613

T. H. THOMAS 1 AUTOMATIC TRAIN SPEED CONTROL APPARATUS Filed April 23.1919 3 sheets-sheet@ .TIMING- Ras,

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may 6 ,1924. 1,492,613

l T.,H. THOMAS O AUTOMATIC TRAIN SPEED CONTROL APPARATUS Filed April 23.1919 5 sheets-Sheet 2 0N n l a N QD`N2-D o;

May 6 1924. 1,492,613

T. H.. THOMAS AUTOMATIC TRAIN SPEED CONTROL APPARATUS Filed Apri; 23,1919 3 sheets-sheet 5 jw= WA IHIIII Im A /13 -/0 /39 n 68 9/0/ /OO g e93 7+ U21/4 /35 /37 J8 65 6756 6F69 4 INVENTOR Thoms H Vhomcs bww/@aPatented liflay 6, i924.

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traitant -ortica THOMAS H. THOMAS, OIE EDGrli/VOOI), PENNSYLVANIA,ASSIGNOR TO THE WESTING- HOUSE AIR BRAKE COMPANY, OF WILMERDING,PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

AUTOMATIC TRAIN-SPEED-CONTROL A'PARATUS.

Application filed April/23, 1919.

To all w/iom t may concern.'

Be it known that I, Ti-roMAs H. THOMAS, a citizen of the United States,residing at Edgewood, in the county of rkllegheny and State ofPennsylvania, have invented new and useful Improvements i-n AutomaticTrain-Speed-Control Apparatus, of which the `following is aspecification.

rIhis invention relates to an automatic l0 train speed controlapparatus, and is in the nature of an improvement oi the constructioncovered by the U. S. Patent No.

1,316,205 of Walter V. Turner, dated September 16, 1919.

`While with an apparatus of the above character, the speed of the tiainis controlled automatically, it is considered desirable for the engineerto be on the alert, and to ensure that he notes the signal indication,one object ot my inventionI is to provide means for imposing a penalty,inthe way of reducing the speed below that required for the particularsignal indication, if the engineer, on passing the signa-l, fails toperiform a required act.

In applying the brakes with the usual fluid pressure brake, if the brakepipe reduction be too light to effect an appreciable reduction inauxiliary reservoir pressure by operation of the triple valve device insupplying iluid from the auxiliary reservoir to the brake cylinder, itmay happen that when the brake pipe pressure is increased' to releasethe brakes, the diierential pressure :S5 will not be suilicient toeffect the release n'iovement of the triple valve pistons.

Another object of my invention is to provide means for ensuring apredetermined reduction in brake pipe pressure under all conditions, andsuliicient to ensure the positive subsequent release oi the brakes uponincreasing the brake pipe pressure.

1i the brakes are released while fluid is still being discharged fromthe brake pipe charge valve mechanism, the brake pipe pressure nothaving had time to equalize throughout the .length of the brakev pipe,shocks are liable to occur, due to the brakes being held applied at theiear end while they are being released at the head end.

Another object of my invention is to overcome this diil'iculty byproviding means for ensuring the substantial equalization of by theoperation of the equalizing dis- Serial No. 292,209.

brake pipe pressure throughout the train before the brakes can bereleased.

Other objects and advantages will ap pear in the following more detaileddescription of the invention.

Inthe accompanying drawings, Fig. 1 is a diagrammatic sectional yview ofan automatic .train speed controlling apparatus embodyinglmy inventionand showing the parts in the positions assumed when the track circuitsare imposing the low speed limit on the apparatus :and the speed ofthetrain is less than the low speed limit; Fig. Q-an'enlarged sectionalview of the penalty `valve portion of the speed controlling apparatus,showing the parts in the positions assumed upon passing a lcaution`signal indication,

-with the penalty push button held depressed by the engineer; Fig. 3 aview similar to Fig, 2, but showing vthe parts in the ypositions assumedif the engineer does not depress the penalty push button upon passing acaution signal indication; Fig. 4 an enlargedsectional view of thevchange speed valve device in 'low speed position; Fig. y5 a similarview of the change speed valve device, showing the same in the mediumspeed position; Fig. 6 an enlareedsectional view of the applicationvalve device in application position; and Fig. 7 a similar view of theapplication valve device, showing the same in lap position.

As shown in Fig. 1 of the drawings, the preferred construction embodyingmy in'- vention may comprise speed magnets A' and B, adapted to becontrolled by track circuits, a speed governor valve portion C, a changeyspeed valve device D, a brake application valve device E, a pei'ialtyvalve device F, a valve device G, a retarded application valve device H,equalizing discharge valve mechanisms K and L, release timing dischargevalve mechanism M, push button penalty valve N, and push button releasevalve 0.

The change speed valve deviceD is for the purpose of determining thespeed limit at which the speed .governor valve portion C will act andcomprises a piston device having connected differential piston heads 1and 2 for operating a slide valve 3. The slide valve has threepositions-a low speed po'- sition, a medium speed position, and anintermediate high speed position.

The brake application valve device E may comprise a piston device havingconnected differential piston heads 4; and 5 for operating a slide valve6.

The speed governor valve portion C comprises a centrifugal device 7 ofthe ordina-ry type adapted to be rotated in accordance with the speed ofthe vehicle by a suitable operative connection to the axle of thevehicle through the pinion 8. The centrifugal device 7 operates asliding stem 9 to which is attached a plate 10 having a series ofadjusting screws 11, 12, 13, 14, and 15 for engaging and operatingrespectively a loiv speed delayed application valve 16, a low speedvalve 17, a medium speed valve 18, a high speed valve 19, and a highspeed delayed application valve- 20.

The penalty valve device F may comprise a piston 21 and a slide valve 22and the valve device G: a piston 23 and slide valve 21.

The delayed application valve device H may comprise a valve piston 25and a poppet valve 26 adapted to he operated by the piston 25.

The speed magnet A controls double beat valves 27 and 28; and the speedmagnet B, the double beat valves 29 and 30.

The brakes may be manually controlled by the usual automatic brake valve81 and independent brake valve 32; thek automatic brake valve 31comprising a rotary valve 33 contained in valve chamber 34 and adaptedto be operated by handle 85 and the usual equalizing discharge valvemechanism 36 for controlling and regulating` the venting ot fluid underpressure from the brake pipe 37, to effect an application of the brakes.

The independent brake valve 32 may comprise a rotary valve 38, containedin valve chamber 39, and adapted to be operated by handle 4:0.

The track circuits for controlling the magnets A and B and the means bywhich the magnets are energized or deenergized, torni no part of myinvention, but it may be stated that a system has been provided so thatlor a clear indication permitting high speed, the magnets A and B areboth energized; for a caution indication permitting medium speed, themagnet A is deenergized and magnet B energized; While for a dangerindication permitting only a loiv speed, both magnets are deenergized.

lVith the usual main reservoir e1 charged with Huid under pressure,liuid is supplied through pipe a2 and passage 113 to valve chamber L14ot' valve device G and from valve chamber 44 through passage 15 to valvechamber 46 ot valve device F.

v From valve chamber 46 fluid equalizes through port 47 in piston 21 topiston chamber 48. Fluid also flows from passage t3 through passage 49to valve chamber 50 of valve device E and from valve chamberl 50 fluidloivs through passage 51 to veuve chamber 52 of valve device l). Fluidunder pressure also equalizes from the valve chamber 50 through therestricted port 96 into piston chamber 85.

The chamber above the equalizing discharge piston and the equaliziugreservoir No. 1 connected thereto, are charged from the brake pipe whenthe application slide valve 6 is in release position, through passage5l, past check valve 55, passage and cavity 57 in slide valve 6 topassage 58.

rlChe eipializing reservoir No. 2 and the chamber above equalizingdischarge piston :59 are also charged through cavity :37 by Way ofpassage 60.

rliming reservoir No. 1 is charged from valve chamber L16, with slidevalve in its inner position, through port 61 and passage 62. Timingreservoir lo. 2 is charged from valve chamber eel of valve device (ilwhen the slide valve 2e is in its innel position, through port 63 andpassage 6ft.

The reduction reservoir No. 1 is connected to the atmosphere in therelease position of application slide valve 6, through passage 65 andcavity 66 to exhaust port 67 and reduction reservoir No. 2 is connectedto atmospheric exhaust port 68 through passage 69 and cavity 70 in slidevalve 6.

In operation, it the signal indication is clear, the track circuitscause both the magnets A and B to be energized, so that the valves 27and 29 are seated and the valves 28 and 30 opened.

The opening' of valve 80 operates to supply liuid under pressure topiston chamber 72 of valve device G from valve chamber 50 throughpassages 71 and 7 3, so that piston and slide valve are shifted to theirinner positions.

rllhe opening of valve 28 ellects the supply ot' liuid to piston chamber7 of the speed limit selector valve device l) 'trom valve chamber 52through passage 7l. passage 75, cavity 76 in slide valve and pesage 77,and also to piston chamber 76 ot piston 2 through the same cavity 76,passage 7i), cavity 8() in slide valve 2a, and passage 61.

As fluid under pressure is thus supplied to the outer faces of thepistons 1 and 2, one or the other ot the spring stops 82 or 83 will movethe valve device to its intermediate or high speed position, dependentupon the position the valve device happens to be in. In the high speedposition of slide valve 3, the passages are blanked which control thetrain for low and medium speeds and the movement of the brakeapplication valve device E is only effected by the high speed valve 19which controls passage 8-1 leading to the piston chamber 85 of pistonf1.

It the speed ot the train should exceed the high speed limit, which maybe 60 milesy per hour, for example, then the speed governor 7 operatesthe stem 9 so as to open the valve 19 and thereby vent fluid from pistonchamber 85. rl"he piston d then shifts the slide valve (S to its outerapplication position, in which the reduction reservoir No. 1, nonv atatmospheric pressure is connected to the charged equalizing reservoirNo. 1 through passage 65, cavity 6G in slide valve G, and passage 58.

rl`he reduction reservoir No. 2, also at atmospheric pressure isconnected to the charged equalizing reservoir No. 2 through passage G9,cavity in slide valve G, and passage GO.

The pressures in the equalizing reservoirs No. 1 and No. 2 are thusvented into the corresponding reduction reservoirs llo. 1

and No. 2 and this permits the higher brakeA pipe pressure acting on theopposite. sides of the equalising pistons 53 and 59 to lift the pistonsand open the corresponding discharge valves 8G and 87. Fluid isthereupon vented Atrom the brake pipe37 to effect an application ot thebrakes throughout the train iu the Well known manner.

Il the speed ot' the train is reduced to the predetermined speed limit,before the equalizing reservoir pressure has fully equalized into thereduction reservoir, it Will still require a little time for the brakepipe pressure to equalize or stabilize throughout the train, especiallyit the train be a long one, and in order to prevent shocks, it isdesirable that no release oi' the brakes take place during this period.Accordingly, the possible release o'f the brakes is delayed for a timein the following manner.

The discharge 'from the equalizing discharge valves 86 and ST, insteadof being vented to the atmosphere in the usual manner is vented to arelease timing reservoir 98, since the opening of either discharge valve8G or 87 vents fluid to a common passage 13T and thence through cavity138 in the slide valve 6, when said valve is in application or lappositions, to passage 139, which leads to the release timingi` reservoir8S and the chamber above the piston 89 of the discharge valve device M.n

The piston 89 operates a discharge valve 98 tor venting iiuid frombeneath the small piston 5 of the application valve device E through apassage 190 to an atmospheric exhaust port 102, so that the releasemovement ot said application valve device is elfected by the action ofthe discharge valve device lvl.

The release of the brakes is controlled by the engineer with certainlimitations and for this purpose the push button release valve device Ois provided.

lli/Then the application valve device E is in application position, thepush button valve 90 controls an exhaust outlet 91, which is connectedto piston chamber 85, through passage 92, avity 93 in slide valve 6,passage 94, and pipe 95. il. spring 96 normally holds the valve 90 open,so that in the application position of the piston Ll, the piston chamberis maintained at atmospheric pressure, so as to prevent the release.movement ot the piston l, until the engineer, desiring to release thebrakes, presses the push button valve to its seat.

This cuts olf the exhaust outlet 91 from the piston chamber 85, but noaction will take place so long the speed ot thetrain exceeds theparticular predetermined speed limit selected, Yin the present instance,the high speed limit. Consequently, the high speed valve 19 continues tomaintain the piston chamber 85 at atmospheric pressurey until the speedhas been reduced to th predetermined speed limit.

So long` as the application valve device E remains in applicationposition, the fluid in the equalizing reservoirs 1 and Q *will continueto equalize into the respective` reduction reservoirs 1 and Q until thepressures become fully equalized.

As soon as the speed of the train has been reduced to the predeterminedspeed limit, the high speed valve 19 is permitted to close and then, thepush button valve 90 being held closed, fluid pressure Will equalizethrough port 9G in piston e to piston chamber 85, permitting the springstop 97 to move the application piston Ll to lap position.

In lap position, the slide valve 6 cuts oli communication from thepiston chamber 85 to exhaust outlet 91, so that the engineer may nowrelease the push button valve 90.

By the movement olf slide valve 6 from application to lap position,communication from the reduction reservoir No. 1 through passage G5,cavity GG, and passage 5S to the equalizingl reservoir No. 1 is cut off,but conimunication 'from the reduction reservoir No. 2 through passage69, cavity 70 in slide valve G, and passagel 60, is maintained, as Wellas communication from the discharge valves 9G and T through passage 13T,cavity 138, and passage 189 to the timingreservoir 88, as will beevident from Fig. 7.

rllhe reduction reservoir No. 1 being cut oil Ytrom the equalizingreservoir No. 1, further reduction in pressure in the equalizingireservoir No. 1 is prevented and When the brake pipe pressure has beenreduced to a degree slightly less than the pressure in said equalizingreservoir, the piston 53 is operated to close the discharge valve 86.

The reduction reservoir No. 2, however, is still in communication Withthe equalizing reservoir No. 2 and the reduction in pressure in'equalizing reservoir No. 2 continues until equalization takes place,and then when the brake pipe pressure reduces to a point slighty lessthan the pressure in said reservoir, the piston 59 operates to closevalve 87.

In the application aswell as the lap position oit the slide valve 6, thecommon discharge passage 137 from the discharge valves 8G and 87 isconnected through cavity 138 in slide valve 6 with passage 139, leadingto the timing reservoir 88.

Se long as the discharge valves 86 and 8i' are venting fluid to thetiming reservoir 88, the piston 89 operates to hold the valve 98 seated,but when the discharge valves close, the pressure in the timingreservoir 88 gradually escapes through an atmospheric vent port 99.'llhe valve 98 controls a passage 100 leading to the piston chamber etpistou of the application valve device E and when the valve device isnot in normal release position, a groove 101 permits the equalization oftluid pressure troni valve chamber to said piston chamber.

This lluid pressure acts on the exposed arca of the discharge valve 98,and when the pressure in the timing reservoir has been re duced to a lowpoint by ven tin g through the port 99, the pressure on the valve 98will litt the valve and permit the venting of :lluid from the smallpiston 5, through passage 100 to exhaust port 102.

lt will be noted that two equalizing dis` charge valve mechanisms areen'iployed and that the equalizing reservoir 01"' the discharge valvemechanism l( is cut oil troni the corresponding reduction reservoir whenthe application slide valve 6 moves to lap position, while theequalizing reservoir oi the discharge valve mechanism L remains inCon'ununication with its corresponding reduction' reservoir. The purposeoi this is to ensure a suiiicient reduction in brake pipe pressure, sayseven pounds, for example, so that there will follow a reduction :inauxiliary reservoir pressure at each triple valve device throughout thetrain, sufficient to cnsure that a subsequent increase in brake pipepressure will be elica-tive to release the brakes ft the reduction inbrake pipe pressure be teo light, then there is daujfer that the brake.pipe pressure cannot be increased suiiiciently te cause such adifferential pressure as to ensure the release movement of the triplevalves. The volume oli the reduction reservoir No. 2 is, of course, suchthat the desired reduction in brake pipe pressure is secured.

Tie reduction of pressure thus produced on piston 5 is sutcient todestroy the equilibrium ot iiuid pressures acting on the ap plicationpiston device, so that the application ,valve device will now be shiftedto re lease position, in which the rotary valve chamber 341 of theengineers brake valve 31 is again connected to the main reservoir byilow from the valve chamber 50, through brake pipe pressure will besomewhat higher than the pressure in the equalizing reservoir No. 1 andin order to effect the quick equalization of pressures on the dischargepiston 53, the eqnalizing reservoir No. 1 is connected in lap positionof the application slide valve 0 with the brake pipe 37, through passage58, cavity 57 in slide valve 6, passage 56, past check valve 55, topassage it the brakes are applied by manipula.- tion ot the engineersbrake valve, the brake pipe pressure is reduced in the usual manner andas brake pipe pressure is present below the equalizing discharge valvepistons 58 and 59, it will be seen that a higher pressure is thenpresent in the equalizing reservoirs 1 and This higher pressure may leakpast the equalizing pistons and 59 after the brakes have been appliedand then tend to release the brakes.

ln order to avoid this possibility, the pistons 52) and 59 are providedwith collapsible valve portions, so that when the equalizing reservoirpressure exceeds the brake pipe pressure, the pistons 53 and 59 will bemoved downwardly compressing springs 107 and 108 so as to open therespective equalizing grooves 109 and 110 and thus permit the quickequalization ot' any excess pressure in the equalizing reservoirs intothe brake pipe.

lt the brakes are released by manipulation el the engineers brake valve,the pressure ou the brake pipe side ot the pistons 58 and 59 increasedand this pressure will litt the pistons and open the correspondingdischarge valves, it the equalizing reservoir l'uessure be less than thebrake pipe pressure.

In order to prevent the. venting of fluid 'from the brake pipe by theopening o't the discharge valves 8G and 87, the discharge passage 137 iscontrolled by the applica-tion slide valve 6, so that in the normalrelease position ot the slide valve, the discharge passage is closed,thus preventing the venting of iiuid from the brake pipe, it thedischarge valves should open.

In the release position of the application slide valve E, the reductionreservoirs 1 and 2 are again connected to the atmosphere while theequalizing reservoirs will be connected to the brake pipe, so as toeffect the recharging' of same with iluid under pressure in readinessior the next operation.

It the signal indication is for caution, the

LaeaeisN apparatus will be adjusted so asto limit the speed to a mediums )eed limit., say miles per hour, for example.

In this case, the track circuits cause the speed magnet A to bedeenergized and the speed magnet B to be energized.

The magnet B being energized, the valve` ture.

According` to this feature,the engineer must perform an act When he seesthat the signal indication is for caution in order to retain the mediumspeed limit permitted under a caution indication. If he does not,whether because he is incapacitated or is inattentive to his duties,then the'speed limit- Will be reduced to the low speed limit.

For accomplishing the above, I provide a penalty valve device N, havinga push button valve 111, which when depressed Will connect the pistonchamber 48 of valve device F with the atmosphere, through passage 112,cavity 113 in application slide valve 6, passage 114, and pipe 115.

The venting'o't fluid from piston chamber 1-8 causes piston 21 lto shiftthe slide valve 22 to its outer position, infy which the piston chamber74 of the speed limit selector valve device D is connected to the valvechamber of valve 2G, through passag'e 77, cavity 116 in slide valve 22,passa-ge 117, cavity 118 in slide valve 24, and passage 119.

-i he chamber above the valve piston 25 of the valve device I-I isconnected to the high speed delayed application valve 20 through passage120, cavity121 in slide valve 24, passage 122, cavity 123 in slide valve22, and passage 124. lllith'the slide valve 22 in its outerposition, asYshown in Fig. 2`of the drawings, the retarded lapplication timingreservoir No. 1 is also connected to the chamber `above the valve piston25 through passage 6.2, cavity 123 in slide valve 22, passage 122,cavity 121 inslide valve 24, and passage 120 and the speed valve 20 isalso connected to the retarded application timing reservoir No. 1through passage 62, cavity iu slide valve 22, and passage 124.

The movement of slide valve 22 to its outer position also connects themagnet valve A to the piston chamber 48, through passage 75. cavity 7Gin slide valve 22, Yand passage 112, so that, the magnet A beingdeenergized. the piston chamber 48 Will be maintained at atmosphericpressure,thus permitting the engineer to release thc penaltyvalve 111. I

The passage 81, leading to piston chamber 78 of valve device rD isconnected through cavity in slide valve 24 with passage 79, but sincethe passage 79 isV novv blanked by slide valve 22, fluid pressure willbe bottled up in piston chamber 78.

The valve 20, being now connected to the charged timing reservoir No. 1,ivill vent fluid'therefrom at a certain rate. This valve is so designedas to vary the vent opening in such a Way that fluid is vented from vthetiming reservoir No. 1 at a rate proportional to the speed of` the trainand when the pressure in the timing reservoir has been reduced to apredetermined degree, the valve device H is operated to vent fluid fromthe small piston 1 of the valve device D, so as to cause the same to beshifted to its medium speed position.

More in detail, when the pressure in the timing reservoir No. 1 isreduced to a prcde termined degree, the feed valve pressure acting onthe under side of the valve piston 25, through pipe 127 and passage 128,lifts the valve piston so as to open the valve 26. The piston chamber 74of the speed valve de-v vice D is then connected to the speed valve 2Oand the timing reservoir No. 1, so that fluid isvented from the face ofpiston 1, permitting the pressure in piston chamber 78 to force thevalve device to its upper or medium speed position. Y

In this position, passage 84, leadingto piston chamber of theapplication valve dc-V vice E is connected, through cavity in slidevalve 3 with passage 126, leading to the medium' speed controlling valve18. If the speed o-fthe Atrain exceeds the medium speed limit, say forexample. 35 miles `per hour, the valve 18 will be in open position, andfluid Will be vented from the pistou chamber 85, to effect the movementof the application valve device E to application'position, in Which thebrakes are appliedv to reducethe speed ofthe train in the mannerhereinbefore described. If the speed ot the train does not exceed themedium speed limit, then the application valve device Will not beoperated. and no action takes place.

As a train will obviously move over a greater distance, before the speedis reduced by applying the brakes, the speed Will be reduced to thedesired speed limit by the time thetrain reaches the' place Where thereduced speed becomes necessary.

The brakes may be released bythe en- `gineer under the samelinfiitationsk as delll() to the d esired speed, the greater the'speedof scribed in connection with running at the high speed limit.

If the engineer does not depress the push button valve 111 in passing acaution indication, then the valve device F will remain in its innerposition, in which the piston chamber 7 S of the valve device D isconnected to the exhaust through passage 81, cavity 8O in slide valve24:, passage 79, cavity 76 in slide valve 22, passage 75, and past theopen valve 27 of the speed magnet A to the atmcsphere.

rlhe piston chamber 7l is also connected to the speed magnet valve 27through passage 77 and cavity 76, but since the piston 2 is of greaterarea than the piston 1, the unbalanced pressure between the pistons willshift the valve device to its lower or low speed position, in whichcommunication is established from the piston chamber of the applicationvalve device E to the low speed valve 17 through passage 84', cavity 129in slide valve 3 and passage 130. y

It will now be evident that if the speed of the train exceeds the lowspeed limit, say 15 miles per hour, for example, the valve 17 Will beopened, and fluid vented from piston chamber 85 to operate theapplication valve device so as to effect an application of the brakes ashereinbefore described.

k'.hus if the engineer fails to depress the push button valve 111 inpassing a caution signal, the speed of the train will be reduced to thelon7 speed limit, instead of the medium speed limit, as would have beenthe case had he depressed the valve,

If the engineer should Wait until after he passes the caution indicationand then press the penalty valve 111, no action vvill take place,because the application valve will noiv be in application position, inwhich the penalty valve 111 is cut off from the valve device F.

If a caution indication is passed and the speed of the train is reducedto the medium s eed limit, as hereinbefore described, and t 1e nextsignal indication is at danger, then a lovv speed indication willafectvthe mag nets A and B at a certain distance in advance of thedanger signal. For low speed, both magnets are deenergized and since thevalve 29 of the magnet B is open, fluid is vented from the pistonchamber 72 of the valve device G, so that the saine will be shifted toits outer position, in Which the lon7 speed delayed application valve 16and the delayed application timing reservoir No. 2 are connected to thechamber above the valve piston 25, by means of cavity 131, whichconnects passage 132, leading to the valve 16, With passages and G4.lllhen the pressure in the delayed application timing reservoir No. 2has been reduced to a predetermined degree by flow past the valve 16, dependent upon the speed of the train andv the naaaeie consequent outletvent area at the valve 16, similar to the action described in conn ctionwith the valve 20, then the feed valve prossure acting on valve pistonwill lift saine so as to open the valve 26 and thus connect the valve 16with piston chamber 78 of the speed valve device D through passage 81,cavity 133, in slide valve 2li, passage 119, and past valve 2G topassage 120, which is nciv connected to the valve 16 as beforedescribed. The speed valve device will therefore be shifted to the loivspeed position by the venting of fluid pressure from the pistou chamber78, and the piston chamber S5 of the application valve device E will beconnected to the loiv speed valve 17, so that if the 'speed of the trainexceeds the low speed limit, and the valve 17 is thus open, theapplication valve device E will be operated to effect an application ofthe brakes. While the operation above described refers to the actionwhich takes place after a caution indication is passed, it Will be understood that the saine action occurs in case the signal indication ischanged from clear or high speed directly to danger indication or lowspeed.

lVhen the application valve device E is shifted to application position,the flow of fluid from the main reservoir to the rotary valve chamber 34is cut off, and there is then some possibility that the brake pipepressure acting below the rotary valve 33 may lift saine from its seat.ln order to prevent this, said valve chamber is connected to the brakepipe in the application position as 'well as the lap position of theapplication valve device by way of passage 54, past check valve .134-,through passage 135, cavity 136 in slide valve 6, to passage 104, Whichleads to thc pipe 105. i It will bc noted in the foregoing descriptionof operation, that when the apparatus is set for louv speed bj, `ieaction of the track signal circuits, the delayed applic;- tion mechanismis brought into action, While if a caution indication is passed Withoutthe engineer operating the penalty push button, the low speed limit iscut in but operates iinn'iediateljf, since the delayed applicationmechanism is then cut out.

llVhen the valve device F is shifted to its outer position, the pistonchamber i8 connected to the speed magnet A, so that if the signalindication should change from caution to clear, the magnet A beingenergized, Will operate to open the valve 28, so as tov supply fluid tothe piston chamber 4S. The piston 21 vvill then shift the slide valve 22to its inner position, in 'which communi lill evident that if therelease valve O be opera-ted to release the brakes, the brakes will bereleased Without Waiting forthe speed to be reduced to the medium speedlimit.

If it is desired to provide an automatic release of the brakes YWithoutaction on the part of the engineer, this can evidently be secured bymerely plugging up passage 94C, leading to the manually operated releasevalve O. c

Having now described my invention, what I claim as new, and desire tosecure by Letters `ljatent, is

l. In a train speed control apparatus, the combination with a brakevalve device for controlling the brakes and mechanism controlled fromthe trackway for imposing a predetermined train speed limit, of meansmanually operable by the engineer independently of said brake valvedevice for permitting a higher train speed limit.

2. In a train speed control apparatus, the combination with a brakevalve device for controlling the brakes and mechanism controlled fromthetrackway for imposing al predetermined train speed limit, of meansseparate from said brake valve device and operable by the engineer toprevent the imposition ot said predetermined train speed limit. Y

3. In a train speed control apparatus, the combination With a brakevalve device for controlling the brakes and mechanism operable to imposea higher or a lovver predetermined train speed limit on the train, ot'means controlled by the engineer separately from the brake valve devicefor setting said mechanism to impose the higher speed limit and meanscontrolled from-the trackyvay for setting said mechanism to impose thelorver speed limit, if the engineer fails to act.V

4. In a train speed control apparatus, the combination with mechanismoperable to impose a higher or a lower train speed limit on the train,of fluid pressure controlled means operable by the engineer for causingsaid mechanism to impose the higher speed y limit and means controlledfrom theftrackivay for causing said mechanism to impose the loiver speedlimit, if the engineer tails to act.

In a train speed control apparatus, the combination with mechanismoperable to impose a higher or a lower train speed limit cn the train,of a brake valve deviceV -for controlling' the brakes, fluid pressurecontrolled means operable independently of said brake valve device forsetting said mechanism to impose the higher speed limit, and meanscontrolled 'from the trackivay for setting said mechanism to impose thelower speed limit, if the engineer fails to operate said fluid pressurecontrolled means.

6. In a train speed control apparatus, the combination with a trainspeed limitselector valve device having positions for imposing differenttrain speed limits, of means subject to track signal control for varyingthe fluid pressure on said selector valve device to determine theposition thereof and a pen-- alty valve device normally establishingconimunication through which said means controls the fluid pressure onthe selector valve device and adapted to be operated by the engineer forcutting oil2 said communication and for independently varying theVfluid' pressure on said selector valve device.

7. In a train speed control apparatus, the combination with a trainspeed limit selector valve device operated by fluid pressure forimposing different train speed limits, of a valve device controlled bythe track signal system for controlling communication through which thefluid pressure is varied on said selector valve device and a valvedevice controlled by the engineer for also controlling communicationthrough which the fluid pressure is varied on said selector valvedevice.

8. In a train speed control apparatus, the combination With a trainspeed limit selector valve device operated by fluid pressure forimposing different train speed limits, of a valve device normallyestablishing communication through which the fluid pressure is varied onsaid selector valve device to move the saine to one speed limitposition, a valve device for applying the brakes at speed limitcorresponding with the position of the selector valve device, and avalve device controlled by the engineer for controlling comtil)munication through Which the fluid pressure K is varied on said selectorvalve device to move same to another speed limit position,

said communication being also controlled* ing to the speed of the train:tor reducing the aressure on said 'a lication valve device of a`manually operated release valve for also i controlling the fluidpressure on said valve device through a communication controlled by saidvalve device 1l. In a train speed control apparatus, thecombinationivith a slide valve, a piston operated upon a reduction influid pressure tor actuating said slide valve to effect an applicationof the brakes, and means controlled equalize the fluid pressures onopposite sides of the piston and speed controlled means for reducing thefluid pressure on said piston, of a release valve operated by theengineer' for closing a vent port to said piston and means for movingsaid piston to lap position upon equalization of fluid pressuresthereon.

13. ln a train speed control apparatus, the

conunnation Winn a oralre application valve` device 'and speedcontrolled means for effecting the n'iovenient thereof to applica-tionposition, of means controlled bv the engineer for effecting the movementof said application valve device to lap position, aud means operatedupon a predetermined brake application for effecting the furthermovement of said valve device to release position.

le. u a train speed control apparatus, the combination with a brakepipe, a valve device for establishing communication for effecting areduction in brake pipe pressure to apply the brakes, and speedcontrolled means for effecting the movement of said valve device. toapplication positioinof means controlled bv the engineer for effectingthe move-ment of said application valve device to lap position and meansoperated upon a predetermined reduction in brake pipe pressure foreffecting the movement of the application valve. device to releaseposition.

l5. ln a train speed control apparatus, the combination with a Vbrakepipe, of an equalizing reservoir, a discharge valve device subject tothe opposing pressures of the equalizing reservoir and the bra-lie pipefor venting fluid from the brake pipe upon a reduction in pressure inthe equalizing reservoir, and a timing reservoir into which fluid isvented from the brake pipe by operation of said discharge valvemechanism. o

16. In atrain speed control apparatus, the combination with a bralrepipe, of an equalizing reservoir, a discharge valve device subject tothe opposing pressures of the equalizing reservoir and the bralrepipefor venting fluid from the brake pipe upon areduction in pressure .inthe equalizing reservoir, an application valve device for controllingcommunication through vhich fluid is Vented from the equaliningreservoir, a timing reservoir into Which fluid is vented from the brakepipe, and means controlled by the pressure in the timing reservoir forcontrolling the movement oi' said application valve device.

17. ln a train speed control apparatus, the combination with a brakepipe, of an equalizing reservoir, adischarge valve device suhject to theopposing pressure-s of the equalizing reservoir and the brake pipe forventing fluid 'from the brake pipe upon a reduction in pressure in theequalizing reservoir, an application valve device for controlling com`nninication through which fluid is vented from the equalizing reservoir,a timing reservoir into Which fluid is vented from the brake pipe andcommunicating with a restricted vent port, and means operated upon areduction in pressure in the timing roservoir for varying the pressureon said application valve device to effect the movement thereof torelease position.

V18. ln a train speed control apparatus, the combination With a brakepipe and a valve mechanism for venting fluid from the brake pipe, of anapplication valve device 'for coutrolling the operation of said valvemechanism and also comi'nunication through which said valve mechanismvents fluid from the brake pipe.

19. in a train speed control apparatus, the combination with a bralrepipe and au application valve device operated When the speed of thetrain exceeds a predetermined speed limit, of an equalizing reservoirand an equalizing discharge valve mechanism suhject to the opposingpressures of the equalizing reservoir and the brake pipe and controlledby said application valve device for venting fluid from the brake pipe,and having the communication. through which fluid is vented from thebrake pipe controlled by said application valve device.

20. In a. traiil speed control apparatus, lhe combination with a brakepipe and an application valve device operated vvhen the speed of thetrain exceeds a predetermined speed limit, of a valve mechanismcontrolled Aby said application valve device for venting fluid ironi thebrake pipe and an additional valve mechanism controlled bv saidapplication valve dcv'ce for also venting fluid from the brake pipe.

2l. ln a train speed control apparatus, the combination with a brakepipe and an application valve device operated when the.

speed of the train exceeds a jnedeterininedspeed limit, of an equahaingreservoir, an

equalizing discharge valve mechanism suhject to the opposing pressuresof the equalizing reservoir and the brake pipe andl controlled bv heapplication valve device for venting fluid from the brake pipe, auadditional. equalizing reservoir, and an additional equaliziug dischargevalve mechanism subject to the opposing pressures of the additionalequalizing reservoir and the brake pipe and controlled by saidapplication valve neeaeia device for also venting Huid Jfrom the brakepipe.

22. In a train speed control apparatus, the combination With a brakepipe and an application valve device operated When the speed of thetrain exceeds a predetermined speed limit, of an equalizing dischargevalve mechanism operated upon movement oi the application valve deviceto application position for venting fluid from the brake pipe andadapted to be cut out ot action upon movement of the application valvedevice to lap position and an additional equalizing discharge valvemechanism operated upon movement of the application valve device toapplication position for venting fluid from the brake pipe and adaptedto remain in ac" tion upon movement of the application valve device tolap position. e

23. ln a train speed control apparatus, the combination with a brakepipe and an application valve device operated When the speed of thetrain exceeds a predetermined speed limit, of an equalizing dischargevalve mechanism controlled by said application valve device foreffecting a limited predetermined reduction in brake pipe pressure andanother equalizing discharge valve mechanism controlled by saidapplication valve device for eliecting a greater reduction in brake pipepressure.

24. In a train speed control apparatus, the

combination With a brake pipe and an ap plication valve device operatedWhen the speed of the train exceeds a predetermined speed limit, of anequalizing discharge valve mechanism open in both the application andlap positions of the application valve device for eecting a limitedpredetermined reduction in brake pipe pressure and another equalizingdischarge valve mechanism open only in the application position ot saidapplication valve device :tor eecting a greater reduction in brake pipepressure.

K 25. ln a train speed control apparatus, the combination with a trainspeed limit selector valve device, of a penalty valve device Jforcontrolling said selector valve device, a manually operated valve forcontrolling said penalty valve device, and an additional valve devicefor also controlling said selector valve device. y

26. In a train speed control apparatus, the combination With anapplication valve device for eliecting an application'oiA the brakes ifthe speed of the train exceeds a predetermined speed limit, of meansoperating to delay the application of the brakes according to the speedof thev train and additional means operating to delay the application ofthe brakes according to the yspeed of the train.

27. lin a train speed control apparatus, the combination with a trainspeed limit selector valve device adapted to impose' diiierent speedlimits, of means operating to delay the operation of said valve deviceaccording to the speed of the train.

28. ln a train speed control apparatus, the combination with a trainspeed limit selector` valve device adapted to impose different speedlimits, of valve means operating to delay the operation oi said valvedevice When the train enters a medium` speed zone, according to` thespeed of the train, and another valve means operating to delay theoperation of said valve device when the train enters a lovv speed Zone,according to the speed of the train.

29. ln a train speed control apparatus, the combination with a brakepipe and an application valve device operating When the speed of thetrain exceeds a predetermined speed limit, of an equalizing reservoirand an equalizing discharge valve mechanism subject to the opposingpressures of the equalizing reservoir and the brake pipe for ventingiuid from the brake pipe, the application valve device being adapted inapplication position to establish communication for venting iiuid fromthe equalizing reservoir and in lap position for supplying Huid i'romthe brake pipe to the equalizing reservoir.

30. In a train speed control apparatus, the combination with a mainreservoir, a brake pipe, and a brake valve device having a valve chambercontaining the usual rotary valve, of an application valve device forconnecting said chamber to the main reservoir in release position and tothe brake pipe in application position.

3l. In a train speed control apparatus, the combination with a trainspeed limit selector valve device, of a valve device for controllingcommunication through which the selector valve device is shifted to themedium speed position upon passing a caution indication and adapted tobe operated by a change in the indication from caution to clear Jforestablishing communication through which the selector valve device isshifted to the high speed position.

32. lin a train speed control apparatus, the combination With a changespeed valve device operated by i'luid pressure and having a medium and ahigh speed position, of a valve device for establishing communicationthrough which luid pressure is varied on said change speed valve deviceto shift same to the medium speed position upon passing a cautionindication, and operated by a change in the indication Jfrom caution toclear for establishing communication through Which fluid pressure isvaried on said change speed valve device to shift same to the high speedposition.

33. ln a train speed control apparatus, the combination With a changespeed valve device operated by fluid pressure, of a Huid itl pressureoperated valve device controlling communication for varying the fluidpressure on said change speed valve device, a track circuit controlledmagnet valve for varying the fluid pressure on the first mentioned valvedevice, a second fluid pressure operated valve device for controllingcommunication for varying the fluid pressure on the change speed valvedevice and a second track circuit controlled magnet valve for varyingthe Huid pressure on said second valve device.

34. ln a train speed control apparatus, the combination with a changespeed valve device operated by fluid pressure, oi a fluid pressureoperated valve device controlling communication lor varying the luidpressure on said change speed valve device, a track circuit controlledmagnet valve Jfor varying the fluid pressure on the rst mentioned valvedevice, a second fluid pressure operated valve device for controllingcommunication for varying the r'luid pressure on the change speed valvedevice, a second track circuit controlled magnet valve for varying thefluid pressure on said second valve device, and a manually controlledvalve for also varying the iluid pressure on said second valve device.

35. lin a train speed controlled apparatus, the combination with a trainspeed limit selector valve device and track controlled means foredecting the movement thereof, oit means for delaying the operation ofsaid selector valve device according to the speed of the train.

36. lln a train speed controlled apparatus, the combination with a trainspeed limit selector valve device and track controlled means foreffecting the movement thereof, of means controlled by the speed of thetrain and interposed between the selector valve device and said trackcontrolled means for delaying the operation of said selector valvedevice for a time interval which is substantially inversely proportionalto the speed ol the vehicle.

37. Railway traffic controlling apparatus comprising apparatus on avehicle controlled from the trackvvay for giving proceed, cau-- tion andstop indications, means controlled by said apparatus for permitting thetrain to travel at high speed when the apparatus indicates proceed andfor imposing a low speed limit when the apparatus indicates stop, meanscontrolled by said apparatus upon changing from proceed to cautionindication for applying the'bralres, a brake valve device forcontrolling the brakes, and manually controllable means separate fromsaid brake valve device for suppressing such brake application andimposing a medium speed limit when said apparatus changes from proceedto caution indication.

38. lailvvay traiic controlling apparatus comprising vehicle-earnedmeans controlled masacre from the trackway for causing certain speedrestrictions upon a change from a more tavorable to a less favorabletrahie condition, a brake valve device for controlling the brakes, andmanually operable apparatus on the vehicle, operable independently ofsaid brake valve device, for suppressing said speed restrictions andimposing less severe speed restrictions it said apparatus is set intooperation before tbe change of tramo condition occurs.

39. Railway tratc controlling apparatus comprising vehicle-carried meanscontrolled from the trackway for causing certain speed restrictions upona change from proceed to caution traffic conditions, and manuallyoperable fluid pressure controlled apparatus on the vehicle forsuppressing said speed restrictions and imposing less severe speedrestrictions if said apparatus is set into gperation before the changeto caution tra c condition occurs.

40. ln a train speed control apparatus, the combination with areservoir, of means controlled according to the speed of the train forventing fluid under pressure from said reservoir and means operated upona predetermined reduction in pressure in said reservoir for determiningthe speed limit of the train.

4l. ln a train speed control apparatus, the combination With areservoir, of means for venting fluid under pressure from the resen voirat a rate proportional to the speed of the train and means operated upona predetermined reduction in pressure in said reservoir for determiningthe speed limit of the train.

42. ln a train speed control apparatus, the combination with areservoir, of a device operated upon a predetermined reduction in luidpressure in said reservoir for determining the maximum speed limit ofthe train and means for reducing the fluid pressure in said reservoir ata rate proportional to the speed of the train. i

43. ln a train speed control apparatus, the combination with tworeservoirs normally charged with fluid under pressure, oi a devicemovable upon a predetermined reduction in pressure in one reservoir toimpose one train speed limit and movable upon a predetermined reductionin pressure in the other reservoir to impose another train speed limitand means for reducing the pressures in said reservoirs according to thespeed of the train.

44. ln a train speed control apparatus, the combination With speedcontrolling means operative upon a change in the signal indication forimposing a lower speed limit, of means operative to delay the operationof said speed controlling means for a time interval which variesinversely as the speed of the train.

45. ln a train speed control apparatus, the combination With a speedcontrolling means having different positions for imposing differentspeed limits on the train and operative upon a change in the signalindication for imposing a lower speed limit, of means operative to delaythe movement of said speed controlling means from a higher to a lowerspeed limit position for a time interval which varies inversely as thespeed of the train.

46. In a train speed control apparatus, the

combination with a train speed limit selector valve device movable todierent positions for imposing different speed limits on the train andtrack controlled means for effecting the movement thereof, of means fordelaying the movement of said selector valve device according to thespeed of the train.

In testimony whereof I have hereunto set my hand.

THOMAS H. THOMAS.

